100HZ数码扫描

100HZ ?? ?? ?¨ ?è
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ù????10ms/312.5=32??s.???????¨?è????????????15625HZ?á????31250HZ,??±??????ú?????¨?è????????,??????50HZ/15625HZ?????????ó??????±??ú??100HZ/31250HZ?¨?è?????????????????????¨??????,?ù?????????ó????±ê×???????64??s,?ù???×?????? 64??s???????????ó??????????32??s??????,???±???á?????????????ó?????????í????????±?,??????????6MHZ??????12MHZ.??×??????ó????????,???????????ó?¨???????ó??????????????,???±?????á???ó,??????????????4???¨?è?????ê??,??????????????,??????????????,??????????????????,??????????????????.????z?ù????    ????????????”?? “??”??”×é??,100HZ??????????????”??”???????á??,???????¨?è?????ò??”??”???????á??,??????????????????”??”??????,???????ó?ü?????ú???¨.    ?÷?áAC-1?ú??100HZ±????¨?è??????IC01??IC02??IC03??IC04??IC06??IC07??IC17?????????????·×é??,????IC01(TDA87550??A/D±????÷,?ü??3??7??9??????????50Hz??Y??U??V????,15??????óé??????,·?±??????·????????óé??,???ó??17????????16MHZ?±??
??????????,Y/50????×?????8bit??×???????24-31??;U/50??V/50(????·???????)????×?????4bit??×???????19-22??????.IC02??IC03(TMS4C2970-26DTR)???????????÷,????IC02?????????¨????/????×÷,??64??s??????????×???????????????32??s??????.IC03??????????????????×??????????????????ó??????????????.IC04(SAA4904H)??????3D???ó???????????á×????¨???·,????A/D±??????????ù?????????ü????????.IC17(SAA7158)???ó?¨?á????×÷???í???·,??100Hz?¨?è??Y??U??V??×?????×?????????????.????A/D±????????????????????????????????°D/A±????????í????,???????????í?÷IC07???????????÷IC06(SAA4951)??±à??????????×÷?ê??.
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????50?????¨?è?????¨??????50HZ??????°×?????é??????±?????°×?×??×??????????????á???????????ó?????????????????????????????á?????????????è???á???????????±?????????????±?????ó???í????????·????á?????????????????¨?è???????í??·??????????¨?è?±???????ü???ü?????ò???ó??????·?±??????á?á???????ó?ü?????ú???????????ü????????
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???ú????PAL??????????????50HZ????????15.625KHZ??100HZ?????????¨????31.5KHZ?????????¨?è????????????°???37.5KHZ??